import sys string = sys.stdin.readline().strip() n = len(string) letter = [[] for i in range(26)] index = [] for i in range(n): ascii = ord(string[i]) if ascii >= 65 and ascii <=90: letter[ascii - 65].append(string[i]) elif ascii >= 97 and ascii <=122: letter[ascii - 97].append(string[i]) else: index.append(i) # print(letter) result = [] for l in letter: if l: result.extend(l) # print(result) for i in index: result.insert(i, string[i]) # print(result) print(''.join(result))